Incident on Kostiantyn Lysenkohttps://lysenko.dev/tags/incident/Recent content in Incident on Kostiantyn LysenkoHugo -- gohugo.ioen© 2026 Kostiantyn LysenkoSat, 21 Sep 2019 19:01:00 +0700MySQL/Percona 5.7+ and indefinitely growing temporary tables on diskhttps://lysenko.dev/posts/2019-09-mysql-5.7-growing-temp-tables/Sat, 21 Sep 2019 19:01:00 +0700https://lysenko.dev/posts/2019-09-mysql-5.7-growing-temp-tables/<p>Some time ago I saw an alert in our monitoring: a production MySQL/Percona server had less than 10% of disk space left. Where did 300 GB of free space go?</p> <p>I found a huge MySQL temporary table on disk. Restarting MySQL fixed it (the temporary table shrank back).</p> <p>The incident was serious enough to warrant a post-mortem. The finding: by default in MySQL/Percona 5.7, temporary tables on disk grow indefinitely.</p>